1. Field of the Invention
This invention relates to the field of electrical connectors, and in particular to an arrangement for providing multiple rows of input/output ports on a printed circuit board or interface card without the need for a stacked multiport connector having an internal shield. The invention also relates to an arrangement for installing a plurality of single row multiport modular jack connectors on a printed circuit board or interface card to form a high density multiport connector array, and to connectors that permit such stacking.
2. Description of Related Art
Electrical connectors known as modular phone receptacles or jacks have been available for many years. Although connectors of this type were originally designed for use in telephone systems, they have found wide acceptance in a variety of other contexts. For example, modular jacks referred to as RJ connectors, which may be incorporated into single port or multiport arrangements, are now commonly used as input/output (I/O) interface connectors for enabling computers to communicate with each other and with a variety of peripheral equipment, and in particular as connectors between a local area network (LAN) and an appropriately configured interface card.
In order to receive a corresponding modular plug, the conventional modular jack or RJ connector is generally made up of a socket housing which includes a plug-receiving opening, opposed top and bottom surfaces joined by opposed side surfaces extending from the opening to a back surface, and a plurality of stamped, metallic elongated contacts mounted in the housing for engaging contacts of the corresponding plug. Each contact in this type of connector includes a contact mating portion at one end extending diagonally into the socket, a vertically extending lead portion at the other end, and a horizontally extending intermediate portion between the contact mating portion and the lead portion. Generally, the lead portions of the contacts are inserted directly into openings in the interface card and soldered in place.
U.S. Pat. No. 5,775,946 (Briones), herein incorporated by reference, discloses a shielded multiport connector having a row of ports capable of receiving RJ-type connector plugs. The connector disclosed in this patent, which is illustrated in FIGS. 1A-1C, uses a single molded housing having multiple openings and a one-piece external shield in order to increase port density without significantly increasing assembly costs.
In particular, as illustrated in FIGS. 1A-1C, the conventional single row multiport RJ connector includes a molded plastic housing 1 and an external shield 2. Molded plastic housing 1 includes a plurality of ports or receptacle openings 3 (shown in FIG. 1B) each accommodating a plurality of contacts 4 including mating portions 5 that extend into the openings to mate with corresponding contacts of an RJ plug connector, intermediate portions (not shown) that extend rearwardly out of the openings, and contact tails 6 that extend vertically from the intermediate portions through the bottom of the connector to be terminated to a circuit board on which the connector is mounted by, for example, mounting posts 7.
Shield 2 is fitted over the housing 1 following assembly of the contacts 4 to the connector and may be secured to the housing in a variety of ways. As illustrated, the shield 2 is a one-piece shield that includes a foldable rear panel 8 that fits over the back of the housing and that includes horizontal extensions 9 from which project latching tabs 10 that engage openings 11 in the bottom of the housing and cooperate with an inwardly extending lower front panel 12 as described in U.S. Pat. No. 5,775,946 to secure the shield directly to the housing, although the present invention may also be applied, by way of example, to one-piece shields in which the foldable rear panel is secured to adjacent side panels of the shield, rather than directly to the housing, and the adjacent panels are secured to the housing, or to shields made up of separate panels. Extending from the shield are circuit board ground tabs 13 and various optionally arranged side, top, and/or bottom ground tabs 14 for engaging a panel and ground tabs 15 for engaging shields of respective RJ plug connectors inserted into openings 3.
As is apparent from FIG. 1B, the openings for the plug connectors are asymmetric. The tops of the openings include notches 16 arranged to receive latching members on the mating RJ plug connectors, and the space remaining at the corners of the housing adjacent the notches may, if required, be utilized to receive LED indicator lights 17 whose terminals 18 extend to the rear and downward in the same manner as the contacts. Although illustrated with the notches at the top of the connector, the orientation of the ports may also be reversed so that the notches and LEDs are located at the bottom of the connector.
In order to further increase port density while maintaining substantially the same footprint on the circuit board, it is known to modify the single row connector by adding a second row of ports, the top and bottom rows of ports all being enclosed by a single common external shield. Examples are disclosed in U.S. Pat. Nos. 5,531,612 (Goodall), 5,562,507 (Kan), 5,639,267 (Loudermilk), as well as in commonly assigned U.S. patent application Ser. No. 09/149,567, filed Sep. 9, 1998.
The adjacent rows of ports in these connectors generally have vertically symmetric orientation, i.e., the notches 16 are at the bottom and top of the connector, in order to minimize the height of the connectors and to prevent the latches in adjacent rows from facing each other, which would make removal of mating plug connectors difficult. As a result, however, the contacts in adjacent rows are close together, resulting in cross-talk between the facing contacts, and necessitating that a shield be placed between the contacts. The difficulty in assembling the contacts and shields to the housing has led to a number of different approaches to stacked multiport connector design, including the modular approach taken in U.S. patent application Ser. No. 09/149,567, but all such designs represent an increase in connector complexity and also in assembly difficulty, that is disproportionate to the increased port density obtained by stacking the rows of the connector.
In addition, because the conventional multiple row multiport connector has a larger number of pins than the conventional single row connector, the number of pins that must be located or aligned with corresponding openings on the circuit board is correspondingly greater, increasing the difficulty of assembling the connector to the circuit board.